Currently, with the rapid development of the display technology, the resolution of the display device is continuously increased. In order to obtain a better display effect of the display device, the array substrate of the display device needs a higher aperture ratio. In the prior art, the aperture ratio of the array substrate is generally increased by reducing the linewidth of the data line, for example, reducing the linewidth of the data line from more than 4.5 μm to 2-3 μm.
In the prior art, the data line of the array substrate is generally formed by a wet etching process. As for the wet etching process, the etch uniformity is proportional to the linewidth of the data line, that is, the narrower the data line is, the worse the etch uniformity is. Specially, when the linewidth of the data line is reduced to 2-3 μm, the worse etch uniformity will result in an opening occurring in the data line, that is, result in a broken data line.
Moreover, as the data line becomes narrower, it is more difficult to repair the broken data line. Thus, after the linewidth of the data line is reduced, the yield of the array substrate is lowed.